Interesting article. The biggest mistake that western critics of hindutva make is assuming that it's a top-down project. IMO this dramatically overstates the influence of Savarkar's ideas on the BJP-voting masses, even those who identify w/ hindutva broadly construed

"Hindutva emerged as the organic response of the Hindu society when faced with new social and political challenges of a rapidly transforming society under capitalist-industrial transformation in the colonial framework"

Think this is broadly correct but would also add that it is a specific response to the political exigencies of the modern democratic nation-state. Extracting concessions from the state requires mass mobilization, which in turns requires some degree of centralization/homogeneity